@article {3907, title = {PT-like phase transition and limit cycle oscillations in non-reciprocally coupled optomechanical oscillators levitated in vacuum}, journal = {Nat. Phys.}, year = {2024}, note = {

Publisher: Nature Publishing Group

}, pages = {1{\textendash}7}, abstract = {

Nanoparticles levitated in an optical trap provide a versatile platform to study mechanical oscillators in a controlled environment with tuneable parameters. Recently, it has become possible to couple two of these optomechanical oscillators. Here we demonstrate the collective non-Hermitian dynamics of such a pair of non-conservatively coupled oscillators. We take advantage of the tunability of the optical interactions between the particles in our system and set the optical interaction between the particles to be purely non-reciprocal. By continuously varying the relative power of the trapping beams, we take the system through a transition similar to a parity{\textendash}time phase transition. A Hopf bifurcation at a critical point results in the formation of collective limit cycle oscillations, resembling those observed in phonon lasers. These coupled levitated oscillators provide a platform for exceptional point optomechanical sensing and can be extended to multi-particle systems, paving the way for the development of topological optomechanical media.

}, keywords = {LF, MF}, issn = {1745-2481}, doi = {10.1038/s41567-024-02590-1}, url = {https://www.nature.com/articles/s41567-024-02590-1}, author = {Li{\v s}ka, Vojt{\v e}ch and Zem{\'a}nkov{\'a}, Tereza and J{\'a}kl, Petr and {\v S}iler, Martin and Simpson, Stephen H. and Zem{\'a}nek, Pavel and Brzobohat{\'y}, Oto} } @article {3754, title = {Synchronization of spin-driven limit cycle oscillators optically levitated in vacuum}, journal = {Nature Communications}, volume = {14}, year = {2023}, pages = {5441}, keywords = {LF, MF}, doi = {10.1038/s41467-023-41129-5}, url = {https://doi.org/10.1038/s41467-023-41129-5}, author = {Brzobohat{\'y}, Oto and Ducha{\v n}, Martin and J{\'a}kl, Petr and Je{\v z}ek, Jan and {\v S}iler, Martin and Zem{\'a}nek, Pavel and Simpson, Stephen H.} } @article {3606, title = {All-optical sub-Kelvin sympathetic cooling of a levitated microsphere in vacuum}, journal = {Optica}, volume = {9}, year = {2022}, month = {Sep}, pages = {1000{\textendash}1002}, abstract = {

We demonstrate all-optical sympathetic cooling of a laser-trapped microsphere to sub-Kelvin temperatures, mediated by optical binding to a feedback-cooled adjacent particle. Our study opens prospects for multi-particle quantum entanglement and sensing in levitated optomechanics.

}, keywords = {LF, MF}, doi = {10.1364/OPTICA.466337}, url = {https://opg.optica.org/optica/abstract.cfm?URI=optica-9-9-1000}, author = {Y. Arita and G. D. Bruce and E. M. Wright and S. H. Simpson and P. Zem{\'a}nek and K. Dholakia} } @article {3478, title = {Stochastic Hopf bifurcations in vacuum optical tweezers}, journal = {Phys. Rev. A}, volume = {104}, year = {2021}, month = {OCT 15}, pages = {043518}, keywords = {LF, MF}, issn = {2469-9926}, doi = {10.1103/PhysRevA.104.043518}, author = {Simpson, Stephen H. and Arita, Yoshihiko and Dholakia, Kishan and Zem{\'a}nek, Pavel} } @article {3368, title = {Entropy Production in an Elementary, Light Driven Micro-Machine}, journal = {Frontiers in Physics}, volume = {8}, year = {2020}, pages = {538}, abstract = {

We consider the basic, thermodynamic properties of an elementary micro-machine operating at colloidal length scales. In particular, we track and analyze the driven stochastic motion of a carefully designed micro-propeller rotating unevenly in an optical tweezers, in water. In this intermediate regime, the second law of macroscopic thermodynamics is satisfied only as an ensemble average, and individual trajectories can be temporarily associated with decreases in entropy. We show that our light driven micro-propeller satisfies an appropriate fluctuation theorem that constrains the probability with which these apparent violations of the second law occur. Implications for the development of more complex micro-machines are discussed.

}, keywords = {KF, LF, MF}, issn = {2296-424X}, doi = {10.3389/fphy.2020.593122}, url = {https://www.frontiersin.org/article/10.3389/fphy.2020.593122}, author = {Box, Stuart J. and Allen, Michael P. and Phillips, David B. and Simpson, Stephen H.} } @article {DonatoNL19, title = {Optical Trapping, Optical Binding, and Rotational Dynamics of Silicon Nanowires in Counter-Propagating Beams}, journal = {Nano Lett.}, volume = {19}, year = {2019}, pages = {342-352}, keywords = {LF, MF}, doi = {10.1021/acs.nanolett.8b03978}, author = {Donato, Maria G. and Oto Brzobohat{\'y} and S. H. Simpson and Irrera, Alessia and Leonardi, Antonio A. and Lo Faro, Maria J. and Vojtech Svak and Marag{\`o}, Onofrio M. and P. Zem{\'a}nek} } @article {SvakNC18, title = {Transverse spin forces and non-equilibrium particle dynamics in a circularly polarized vacuum optical trap}, journal = {Nature Commun.}, volume = {9}, year = {2018}, pages = {5453}, keywords = {LF, MF}, doi = {10.1038/s41467-018-07866-8}, author = {Vojtech Svak and Oto Brzobohat{\'y} and M {\v S}iler and P J{\'a}kl and J. Ka{\v n}ka and P. Zem{\'a}nek and S. H. Simpson} } @article { SimpsonNL17, title = {Optical Binding of Nanowires}, journal = {Nano Lett.}, volume = {17}, number = {6}, year = {2017}, pages = {3485-3492}, keywords = {LF, MF}, doi = {10.1021/acs.nanolett.7b00494}, author = {S. H. Simpson and P. Zem{\'a}nek and Marag{\`o}, Onofrio M. and Jones, Philip H. and Hanna, Simon} }